Figure 7.2.1 Gas Valve Adjustments - Hamworthy MILBORNE381 Series Design Installation, Commissioning And Operating Instructions

7.2 Checks prior to lighting the boiler
Note: Refer to Appendix A, Gas Data Tables, for maximum inlet pressure for normal operation.
7.2.1 The Following checks must be made prior to lighting the boiler;
1. Remove the front cover to gain access to the boiler components. The cover is secured with 2 screw on the
underside at the left and right hand sides. Once the screws have been removed the cover may be lifted to
disengage the retaining clips at the top and removed. Store the front casing panel carefully to prevent damage.
Note: Before starting the boiler commissioning procedure verify the following;
2. Ensure that all external controls are not demanding that the boiler commences operation.
3. Make certain that the boiler is configured for the appropriate gas being supplied. Parameter 36 must be
checked and set as necessary. When the boiler arrives on site parameter 36 is configured for Natural Gas supply
with equivalent flue length less than 15 metres. If using the boiler with a LPG Gas supply or equivalent flue
lengths greater than 15 metres, parameter 36 must first be modified in accordance with the table below.
Instructions detailing the procedure for modifying parameters are given in Section 8.9 of this manual.
Parameter
Description
Range
Default
Specification 1=Natural Gas with equivalent
flue length <15m
2=Natural Gas with equivalent
flue length >15m
3=LPG with equivalent flue
length <15m
4=LPG with equivalent flue
length >15m
9. Turn on the mains gas supply. Check that
sufficient gas pressure is available at the boiler,
17.5mbar Natural Gas, 37.5mbar LPG.
10.Ensure that all electrical connections made to the
boiler are correctly sized and installed. Refer to
wiring diagrams in Section 9.3.
11 Check that the boiler controls wiring has not been
modified. Any modification could lead to boiler
failure.
7.2.2 Gas inlet pressure test
The gas pressure must be checked at the inlet to the
boiler as shown in figure 7.2.2. This is to ensure that
the gas pressure is both constant and sufficient to
provide full burner output. To verify this the pressure
has to be taken as a static and a dynamic reading.
The dynamic reading cannot be taken until the boiler
has been started - refer to 7.3.3
A maximum difference in gas pressure of 1 mbar
must not be exceeded between static and dynamic
conditions.
The gas pressure measured during these tests must
be no less than 17.5 mbar for Natural Gas or 37.5
mbar for LPG.
HAMWORTHY HEATING LTD
36
Type of Gas
1-7
1
MILBORNE
4. Check that the heating system has been flushed and
refilled and that air has been purged from all high points.
5. Ensure that the system isolating valves are in the
open position and that the water pressure within the
heating system is correct. Minimum pressure 0.5barg.
6. Ensure that circulating pumps have been installed
correctly and that the pumps are available for operation.
7. Ensure that the flue ducts are correctly fitted and that
they are free from obstruction. Check that the inlet and
outlet terminal are located correctly and in accordance
with regulations.
8. Ensure that the gas supply has been properly purged
and verified for gas soundness. A purge and soundness
certificate should be available from the gas pipework
installation contractor.
Gas inlet
pressure test
point
Gas valve
throttle screw
Fig 7.2.1 Gas valve adjustments
22
Gas Valve
offset
adjustment
Gas outlet
pressure test
point
500001130/J